Radiation exposure from medical imaging has dramatically increased in recent decades. The average per capita radiation dose from medical imaging in the U.S. has increased six-fold over the last thirty years. This increase is of great concern to the public, medical community and regulatory agencies, and it has been identified as an important patient safety issue. Children have compounded risk associated with radiation exposure. The longer life expectancy of children as compared to adults provides a larger window of opportunity for expressing the damaging effects of ionizing radiation. In addition, epidemiologic studies of exposed populations demonstrated that children are considerably more sensitive to the carcinogenic effects of radiation.
Fluoroscopy, a form of medical radiation, is used to guide millions of medical procedures each year. For example, cardiac catheterizations are currently performed using fluoroscopy, which requires constant visualization of catheter manipulation by exposing the patient to ionizing radiation. While these important medical procedures can be lifesaving, the concomitant radiation exposure places the patient at risk for development of radiation-induced disease.
Children with congenital heart disease (CHD) are especially vulnerable. Many therapeutic interventions for CHD patients have transition from open surgical procedures to minimally invasive, catheter-based procedures requiring fluoroscopic guidance. While this trend has many benefits, it unfortunately results in excessive cumulative radiation exposure to children who often undergo multiple, complex catheter procedures. Moreover, recent studies in children with CHD who have undergone catheterization have demonstrated direct DNA evidence of long-lasting chromosomal damage. This alarming evidence underscores the need for an alternative to ionizing radiation to guide cardiac catheterizations in children.
To date, radiation dose reduction in cardiac catheterization has been aimed at modifying the existing technology to limit dose delivery. However, this approach is inherently limited because fluoroscopy remains the principal imaging modality.